A former Thai navy diver who joined the effort to rescue 12 boys and their coach trapped in a flooded cave in Thailand has died.
Officials said he ran out of oxygen and lost consciousness on his way out of the Tham Luang cave complex after delivering supplies to the group.
The diver had left the navy but had returned to help with the rescue operation.
His death highlights the dangers of the operation to extract the team from deep inside the waterlogged cave, raising questions about the feasibility of bringing youngsters out the same way.
“A former Seal who volunteered to help died last night about 2am,” said Passakorn Boonyaluck, Chiang Rai deputy governor, calling it “sad news”.
The diver, identified as Saman Kunont, was coming back from a spot inside the Tham Luang cave where the group were located on Monday when his supplies ran short.
“On his way back he lost consciousness,” said Apakorn Yookongkaew, Thai Seal commander, adding that a friend had tried to help bring him out.
“But even though we have lost one man, we still have faith to carry out our work.”
The death is the first major setback since the boys were found alive after nine days trapped inside the flooded cave complex on Monday.
Two British divers made the breakthrough as they led Thai Navy searchers into the furthest reaches of the caves.
The boys and their coach were in remarkably good shape, despite their ordeal.
Divers have been back and forth delivering food and medicine, as well as oxygen tanks as they prepare to extract the team.
The Thai navy is teaching the boys the basics of diving, with a view to guiding them out through the flood waters.
But high water levels inside the cave and flooded passageways are complicating the effort, and would force the boys to dive alone in places.
Cave rescue experts have said it could be safest to simply supply the boys where they are for now, and wait for the water to go down either naturally or by pumping. That could take months, however, given that Thailand’s rainy season typically lasts through October.
But that brings its own difficulties, according to Paul Auerbach, of the Department of Emergency Medicine at Stanford University’s medical school.
“Being discovered was a moment of elation,” he said, “but that is now followed by the reality that a difficult technical rescue might be necessary, which carries with it disappointment for the boys and a new set of fears.”